What can you say when Russia's main intelligence service raids its main law-enforcement agency and arrests some of its top officials for ties to organized crime?

Because that's what happened yesterday when the FSB arrested the head of the Investigative Committee's Moscow branch, as well as the head and deputy head of its Internal Affairs division, accusing them of taking bribes from a notorious mob kingpin.

Well, what you most definitely cannot say is that this is part of some crackdown on corruption and mob ties in law enforcement.

Russia's security services, of course, have long worked hand in glove with organized crime and will continue to do so.

And those arrested yesterday for mob ties could easily have said: "I know you are, but what am I?!"

No, cases like this are never about what is on the surface.

The criminal charges -- which could easily have been levied against anybody -- are almost always a smokescreen for a political battle below the surface.

And what yesterday's raid and arrests suggest is that yet another "siloviki war" -- a battle among Russia's security services -- may be under way.

Elections are on the horizon. Vladimir Putin is hedging his bets by creating a 400,000-strong National Guard that answers to him alone. And everybody appears to be getting nervous.

Russian opposition figure Roman Dobrokhotov summed it all up rather succinctly in a tweet yesterday:

"The cops are afraid of the prosecutors, the prosecutors are afraid of the Investigative Committee, the Investigative Committee is afraid of the FSB, the FSB is afraid of Ramzan Kadyrov, Kadyrov is afraid of Vladimir Putin, and Putin is afraid of everybody."